refactor(FN-2162): rename kb-agent identifiers to fn-agent

- Rename core loader, dashboard server chat/planning routes, and frontend agent IDs/storage keys from kb-agent to fn-agent naming
- Update dashboard hooks and components (agent list, chat view, quick chat) to use the new fn agent key prefixes consistently
- Refresh engine, dashboard, core, and CLI tests/mocks to remove remaining kb-agent route and temp prefix references
- Update storage/gap-analysis docs to reflect fn agent key names and add a @gsxdsm/fusion patch changeset for the rename

packages/cli/src/commands/agent-export.test.ts

@@ -14,7 +14,7 @@ vi.mock("../project-context.js", () => ({
 import { runAgentExport } from "./agent-export.js";
 
 describe("agent-export", () => {
-  const tmpRoot = join(tmpdir(), `kb-agent-export-test-${process.pid}`);
+  const tmpRoot = join(tmpdir(), `fn-agent-export-test-${process.pid}`);
   let projectDir: string;
   let outputDir: string;
 

packages/cli/src/commands/agent-import.test.ts

@@ -106,7 +106,7 @@ function createHierarchyCompanyDirectory(basePath: string): string {
 }
 
 describe("agent-import", () => {
-  const tmpDir = join(tmpdir(), `kb-agent-import-test-${process.pid}`);
+  const tmpDir = join(tmpdir(), `fn-agent-import-test-${process.pid}`);
   let createAgentMock: ReturnType<typeof vi.fn>;
   let listAgentsMock: ReturnType<typeof vi.fn>;
   let initMock: ReturnType<typeof vi.fn>;